Abstract:
Adequate control of CO2 emissions may require a significant increase in energy price, which in turn wilt create long-term economic costs. This paper explores the effects of long-term productivity trends in the U.S. economy and relates them to the cost of reducing CO2 emissions. Technology change has been negatively correlated with energy prices and positively correlated with materials prices. Thus, if all prices remain constant expenditures on materials per unit of output will decline, and expenditures on energy per unity of output will increase. If energy prices increase, the rate of productivity growth will decrease. This trend will be very small, if measured on an annual basis, but eventually could be quite significant. A comparison with recent cost estimates of CO2 emission control suggests that this otherwise ignored productivity effect could be the largest component of a complete cost analysis.

Abstract:
In this paper we describe a case study for Sri Lanka that explores a wide range of options for reducing greenhouse gas (GHG) emissions. Options range from renewable technologies to carbon taxes and transportation sector initiatives. We find that setting electricity prices to reflect long-run marginal cost has a significant beneficial impact on the environment, and the expected benefits predicted on theoretical grounds are confirmed by the empirical results. Pricing reform also has a much broader impact than physical approaches to demand side management, although several options such as compact fluorescent lighting appear to have great potential. Options to reduce GHG emissions are limited as Sri Lanka lacks natural gas, and nuclear power is not practical until the system reaches a much larger size. Building the few remaining large hydro facilities would significantly reduce GHG emissions, but these would require costly resettlement programs. Given the inevitability for fossil-fuel baseload generation, both clean coal technologies such as pressurized fluidized bed combustion, as well as steam-cycle residual oil fueled plants merit consideration as alternatives to the conventional pulverized coal-fired plants currently being considered Transportation sector measures necessary to ameliorate local urban air pollution problems, such as vehicle inspection and maintenance programs, also bring about significant reductions of GHG emissions.

Abstract:
This paper summarizes results from ten global economy-energy-environment models implementing mechanisms of endogenous technological change (ETC). Climate policy goals represented as different CO2 stabilization levels are imposed, and the contribution of induced technological change (ITC) to meeting the goals is assessed. Findings indicate that climate policy induces additional technological change, in some models substantially. Its effect is a reduction of abatement costs in all participating models. The majority of models calculate abatement costs below 1 percent of present value aggregate gross world product for the period 2000-2100. The models predict different dynamics for rising carbon costs, with some showing a decline in carbon costs towards the end of the century. There are a number of reasons for differences in results between models; however four major drivers of differences are identified. First, the extent of the necessary CO2 reduction which depends mainly on predicted baseline emissions, determines how much a model is challenged to comply with climate policy. Second, when climate policy can offset market distortions, some models show that not costs but benefits accrue from climate policy. Third, assumptions about long-term investment behavior, e.g. foresight of actors and number of available investment options, exert a major influence. Finally, whether and how options for carbon-free energy are implemented (backstop and end-of-the-pipe technologies) strongly affects both the mitigation strategy and the abatement costs.

Abstract:
Using a global dynamic optimization model that includes a notion of endogenous energy-saving investments, economic impacts and energy-system changes are assessed under several policy cases where CO2 concentration is stabilized at the 450, 500, and 550 ppm levels by the year 2100. The effect of increased investments in energy-saving technologies on energy efficiency is derived exogenously from results of the AIM/Enduse model applied to Japan, then endogenized in the global dynamic optimization model.We find that with diffusion of energy-saving technologies, GDP loss during the 21st century falls from 2.5% to 2.1% in the 450 ppm case. The impact is small for the 550 ppm case, however, because a shift to low-carbon-intensive energies such as gas and renewable energies does not occur to a significant extent under this target.

Abstract:
This paper compares both the main physical options and the principal policy instruments to realize a deep cut in carbon dioxide emissions necessary to control global climate change. A top-down energy-economy model is used that has three emission reduction options: energy savings, a transition towards less carbon-intensive or non-carbon energy resources, and the use of carbon dioxide capture and storage technology. Five policy instruments - carbon taxes, fossil fuel taxes, non-carbon (renewable) energy subsidies, a portfolio standard for the carbon intensity of energy production, and a portfolio standard for the use of non-carbon (renewable) energy resources - are compared in terms of costs, efficiency and their impact on the composition of the energy supply system. One of our main conclusions is that a carbon intensity portfolio standard, involving the recycling of carbon taxes to support renewables deployment, is the most cost-efficient way to address the problem of global climate change. A comprehensive introduction of the capture and storage of carbon dioxide would contribute to reducing the costs of climate change control, but would not obviate the large-scale need for renewables.

Abstract:
Large but temporary price increases are sometimes deployed on days when the demand for electricity is extremely high due to exceptionally warm or cold weather. But what happens when the extreme price changes are permanent? Between January 2013 and April 2016, natural gas and electricity prices in Ukraine increased dramatically (up to 300% of the initial rates). We exploit variation in tariffs over time and across customers to estimate the price elasticity of electricity demand using a panel dataset with monthly meter readings from households in Uzhhorod in Ukraine. The price elasticity of electricity demand is -0.2 to -0.5, with the bulk of our estimates around -0.3. The elasticity becomes up to 50% more pronounced over the first three months since prices change. We find only limited evidence that persons who are attentive about their consumption levels, their bills, or the tariffs are more responsive to the price changes.